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    <title>Document</title>
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<script>
    function sz(ary){
        var newAry=[];
        for(var i=0;i<ary.length;i++){
            var item=ary[i];
            if(newAry.indexOf(item)==-1){
                newAry.push(item);
            }
           
        }
        return newAry;
    }
    var ary1=[1,2,3,2,1,3];
    var res=sz(ary1);
    
    
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